Requests for new libraries and modifications to existing libraries come from the Boost and C++ community. The page http://www.boost.org/more/requesting_new_features.htm describes how to request a new feature.
There are technical requirements on each library, see Library Technical Requirements for more information.
Automated regression (http://www.boost.org/more/regression.html) tests are run on the Boost product with the results available by the website. Test reports are available for all currently supported Boost versions and the current development tip.
The maintainer for each library examines the regression tests and considers and changes may be needed. When a release is in prepartion the Release Manager liases with the library maintainers over regression test failures.
A new version of the Boost product is released approximately every six to 12 months. The process of refining the development source to a release is described in the (http://www.boost.org/more/release_procedures.htm) Release Procedures.
A release is run by a Release Manager who is responsible for following the Review Manager's Checklist (http://www.boost.org/more/release_mgr_checklist.html). A Release Manager is chosen by the Boost community.
Support for Boost users is provided primarily through the Boost-users mailing list. Help on library usage, installation and compiler issues is available from the Boost community and library maintainers through the mailing list.
If a user believes he has found a bug it can be reported through the mailing list or via the bug tracking facility. Some developers may be able to fix a bug in the development code themselves. See What to Do About Bugs (http://www.boost.org/more/bugs.htm)
Commercial support is also available.
If a bug is confirmed it will be assessed and fixed by the library maintainer with the assistance of the Boost community. The code changes (if any) will be made to the development source.
Normally there are no "patches" or "service packs" to Boost releases. If the community deem it necesary then a minor release may be made. This follows the normal release procedures with the Release Manager deciding which changes should be included in the minor release.
Since a library user has the source code he can merge bug fixes to his own copy to fix prior to a new Boost release.